Self-Sealing Pneumatic Pressure Vessel With Passive and Active Methods

This paper discusses passive and active self-sealing techniques for pressure vessels. The history and state-of-the-art of self-sealing fluid containment vessels is followed by a discussion of challenges specific to implementing self-sealing on pressure vessels. These challenges include large pressure differentials, high speed flows through the leak, the need for relatively rapid response, and embedding the sealing techniques as a composite within a pressure vessel while satisfying practical constraints of weight and size. A benchtop pneumatic test bed provides a setting for evaluating self-sealing technologies. Testing focuses on experiments and models of passive techniques that use shear-thickening fluid coagulation for plugging. This is followed by results that demonstrate the use of active sealing methods with coordinated leak sensing and activated sealing. Acoustic emission (AE) monitoring detects the leak. Electrocoagulation and thermoplastic flow provide the means of controlled sealing. A separate study explores AE testing as a tool for damage assessment. Combining AE testing with neural-network pattern recognition algorithms enables leak detection, location, and size assessment.